Not so much high strung as high energy and high stamina.
Professional dogsled racers, the kind that compete in and win the iditarod and similar races cross traditional sled dog breeds with both English and German pointers to add speed and stamina, which should tell you a bit about how much energy and stamina a full blood pointer has.
ANY dog that isn't getting it's energy drained is going to appear high strung. The pointer breeds just take a lot more exercise to drain. Most breeds need exercise equivalent to around a 30 minutes walk once a day...and unfortunately too many get just a 10 minute walk. Pointers need roughly double what the average dog needs. They are also less keyed in on fetching, so that eliminates a common secondary way to burn energy off.
What this really means is it gives you a license to be more intense with the pointers. You don't have to take him for a 60 minute walk when a 5-10 minute walk to get his muscles warmed up followed by 10 minutes of him tearing it up behind you as you bike as fast as you can. Heck, a 10 minute walk to an open field where you can read a book and he can spend a half hour racing around smelling things is good too, provided it's a relatively new environment every time. (No, putting him out in the back yard doesn't count, he already knows every square inch of that place)
A tired dog is a good dog. This goes double for pointers